Saw



patented Mar. 31, i925,

UNITED STATES 1,531,575 PATENT OFFICE.

FRANK GODFREY MATTSON, OF KOTUKU, WESTLAND, NEVI` ZEALAND.

. SAW.

Application filed November 7, 1924. Serial No. 748,455.

To all yLU/0m it 71mg/ concern.'

Be it known t-hat I, FRANK GODFREY lS/Li'r'rsoN, subject of the Kingv of Great Britain, residing at Kotuku, `Westland, in the Dominion of New Zealand, have invented new and useful Improvements in Saws, of which the following is a specification.

This invention relates to an improved formation of saw blade adaptable for all classes of saws whether hand saws, gang saws, circular saws, band saws, cross-cut saws, or the like. It has been devised with the object of providing a formation or construction of cutting edge that will allow of the saw being used with equal effectiveness for either cross-cut or rip work and to cut as the bladel is moved in both directions.

The invention therefore consists in constructing the blade with teeth of special formation by means of which these results are obtained.

This forinationis shown in the accompanying drawings, inwhich Figure l is a side elevation of a portion of an ordinary saw blade having its teeth constructed in accordance herewith.

Figure 2 is a similar view of a portion of a circular saw.

Figure 3 is a detail side elevation of some of the teeth, drawn on an exaggerated scale.v

Figure 4l is a cross sectional elevation on thc line 4 4 of Figure 3.

The invention is carried out by forming the blade edge withA a. number of equally spaced major -tceth A, divided from one another by means of clearance slots B of approved width and depth, and in forming cach major tooth A with four specially shape/.l and disposed smaller' teeth C. These sn'iallcr teeth C are spaced evenly apart and are made. of equal width and each is shaped of narrow right-angled triangular form at its point so that one edge c is made to extend out at aight angles to the line ofthe blade while then other c inclines inwards from thel apen or point. The side face of each inclined edge is also bevelled as at c so that, with the point, a fine cutting edge is formed.

The four small teeth C of each major tooth are arranged relatively so that they forni pairs, two teeth together having their straight edges c facing in one direction and the other two having theirs facing in the other direction. This arrangementv differs edges c operate while in ripping,

in order with the small teeth of the next 1na.]or tooth, so that throughout the saw length, thel small teeth are arranged inpairs 'i with those of each pair having their cutting edges c facing in the opposite vdirection tol those of the pairs neXt in order to it.V The two teeth of each pair also have their'cutting bevels 02',disposed 'on respectivelyv opv f posite faces of vthe blade, and in addition,

'are set outwards on the opposite faces,

application of the invention to circular saws y. will permit of the saw being driven to rotate in either direction and to cut as eliticiently in both, and also for the saw having its faces reversed upon its spindle. y l

The spaces or gullets B provide for the collection and clearance of the saw dustl in the sawsoperations so that no choking can take place.

T claim zjanibing or- A saw blade constructed wit-h its cutting i edge formed with a number of major teeth of equal width divided by clearance vslots and each of which major teeth is formed with four smaller teeth evenly spacedrv apart and of equal width, and each shaped with a point of right angled triangular form, each four smallteeth being so arranged with respect to themselves and thoseof the adjacent major teeth, that throughout the length of the cutting edge, the small teeth are arranged in pairs with those of one pair having the angular edges of their poin facing in the opposite direction to 'those'of the pairs on eachy side of it. and in which each small tooth has its angularedgebevelled on the opposite face kof the blade to that on which the teeth next in order to it are bevelled, substantially as specified.

In testimony whereof, T affix my signature.

` FRANK GODFREY MATTsoN. 

